According to People, the collection will include sportswear, denim and activewear fit for the fashion-conscious tween, and is set to hit stores this fall. Jessica and Ashlee will serve as the collection's co-creative directors.

"Creating a tween apparel collection was a natural extension for the brand. I'm excited to bring my sister, Ashlee, along as co-creative director of this division, because she brings a savvy rocker edge that defines today's tweens," Jessica told WWD. Ashlee adds, "My goal as co-creative director will be to design clothes that will help inspire young girls to express their personalities and creativity through fashion."

The Jessica Simpson Collection, which includes women's shoes, dresses, sunglasses and swimwear, helped the singer's fashion sales total $750 million in 2010, according to New York Magazine. Meanwhile, Jessica Simpson's last release, the 2010 holiday-themed "Happy Christmas," has sold 28,000 copies, according to Nielsen SoundScan.